Improvement in stone-crushers



T. A. BL Q Stone-0 1111 er.

No; 221,768. Patented Nov.18, 1879.

UNITED STATES PATENT QFFICE,

THEODORE A. BLAKE, OF NEW HAVEN, CONNECTICUT.

IMPROVEMENT IN STONE-CRUSHERS.

Specification forming part of Letters Patent No. 221,768., datedNovember 18, 1879; application filed October 16, 1879.

To all whom it may concern Be it known that I, THEODORE A. BLAKE, of NewHaven, in the county of New Haven and State of Connecticut, haveinvented a new Improvement in Stone-Crushers; and I do hereby declarethe following, when taken in connection with the accompanying drawin gsand the letters of reference marked thereon, to be a full, clear, andexact description of the same, and which said drawings constitute partof this specification, and represent, 111- Figure 1, a plan or top view5 Fig. 2, longitudinal section.

The object of my invention is 'to construct a stone-breakin g machine inwhich the tensile strains due to the performance of its work shall bealmost wholly upon wrought-iron or steel, instead of cast-iron, givinglightness and strength combined, and to provide for the adjustment ofthe opening at the bottom of the jaws and the length of stroke of themovable jaw withoutthe substitution of parts, and also to provideagainst breakage from undue and excessive strains to which such machinesare likely to be subjected.

The invention consists in the introduction of an elastic or yieldingmaterial between the point where the power takes its bearing and the jawto which the power is applied; also, in combining in a stone-breakingmachine a pitinan adjustable as to its length, with a toggle-blockadjustable on the rods which connect the front and rear parts of themachine, in this case the toggle-block being said rear part.

A is a three-sided frame-work of cast-iron or steel with broad flangedbase resting upon thin elastic cushions or placed between it and the twoparallel timbers B B upon which it is supported. This casting forms thefront and two sides of the jaw-opening A, and affords a support for theshaft b, on which the swing or movable jaw A is suspended, and, togetherwith the movable jaw A constitutes the upright convergent jaws of thewell known Blake stone-breaker. Holes in the sides of this casting areleft or bored to receive the main tension-rods of the machine E E, andit is held in position on the parallel timbers by means of bolts orscrews passing through the bottom flanges.

C C are wrought-iron or steel clamps, one on each side of thejaw-opening, which serve to take a portion of the strain due to thecrushing of material in the upper portion of the jaws to ,hold the shaftof the movable jaw in position, and to form a part of the walls of thejaw-opening. These clamps may be closely fitted or bolted onto the castframe, or both.

D is "a casting of iron or steel forming the back end of the machine ortoggle-block,

.against'which one endof a toggle of the toggle-joint hereinafterreferred to abuts, and which is perforated with holes corresponding tothose in the front casting to receive bolts of wroughtiron or steelforming the main tension-rods E E above referred to. Thisrcasting I)also rests upon elastic cushions a on the parallel timbers which supportthe front cast- 111g.

The main tension-rods E E may be either round, square, or flat bars.They connect the front and rear castings and are provided with screwthread and nuts, or with some equivalent arrangement, by means of whichthe position of the rear part D with reference to the front part A maybe adjusted as desired.

The necessary short vibrating motion of the swing-jaw is derived fromthe toggle or elbow joint between the back of the movable jaw suspendedin the front part and the rear part, which, for convenience, maybecalled the toggle-block. This toggle-joint is worked by means of aneccentric or crank shaft, Gr, through the pitman hereinafter described,which connects the toggle-joint and main shaft. The main shaftis held inposition and revolves in bearings I bolted onto the under side of thetimbers B B on which the front and rear parts of the machine arecushioned and supported.-

The pitman connecting the shaft and the toggle-joint consists of ablock, F, in which the main eccentric or crank shaft works; wrought-ironor steel rods L L screwed, cast, or keyed into the said block; thepitmanhead H, in which are holes to receive the rods L L and which isfree to slide up and down on said rods; spiral springs N N on the rods;and the nuts n n above the head to hold the head-block in position. Theobject of the spiral springs is to cause the pitman-head to follow whenthe nuts are unscrewed. They may be replaced by nuts on the rods, bymeans of which the position of the pitinan-head on the rods may beadjusted as desired.

Oil-holes drilled through the length of the pitman-rods furnish aconvenient means of oiling the main shaft.

In operation the toggle-joint works only on one side of a line joiningthe toggle-bearing in the movable jaw, and the togglebearing in the maintoggle-block or rear part of the machine.

The stroke of the jaw will depend upon the length and inclination of thetoggles, as well as upon the eccentricity of the shaft.

If the pitman-head be so adjusted as to bring the toggles into line atthe end of the forward stroke of the movable jaw, the minimum strokewould be employed.

The proportion adopted in making a working stone-crushing machine issuch that when the toggles are brought into a straight line the strokeof the jaw would be hardly appreciable; but if, by means of theadjustment of the pitman-head on the rods, we give the toggles aninclination of five degrees-say, at the end of the forward stroke of themovablejawand then revolve the shaft, the inclination of the toggles toa line joining the toggle-bearing in the movable jaw, and thetoggle-bearin g in the toggle-block will, of course, increase until theend of the backward motion of the jaw is attained. We shall then findthe length of the toggles and eccentricity of the shaft remaining thesame; that the motion of the movable jaw, instead of being hardlyappreciable, would be nearly one-half an inch-a stroke sufficientlygreat for practical work of stone-breaking on a large scale. Astillgreater inclination of the toggles would give a longer stroke.

To illustrate by example the increase of stroke of the movable jaw bythe increase of inclination of the toggles by means of the adjustment ofthe pitman-hcad, let us suppose the eccentricity of the shaft to befive-eighths of an inch. The stroke of the pitman would be one andone-quarter inch. Suppose the toggles to be of equal length, and thatlength fitteen inches. The stroke of the movable jaw, when thepitman-head is adjusted so as to bring the toggles into line at the endof the forward stroke of the jaw, would be equal to the sum of theversines of the are through which the ends of the toggles bearing on thepitman-head move. The sine of the are would be equal to the stroke ofthe pitman-z'. 0., one and one-fourth inch, and the inclination of thetoggles at the back end of the stroke of the movable jaw would be fourdegrees fortyseven minutes.

The length of stroke of the movable jaw would be about one-tenth of aninch, or practically nothing. If, now, we set the pitmanhead so that thetoggles, when the end of the forward stroke of the jaw is attained,shall be inclined to the line joining the bearings on the swing-jaw andmain toggle-block at an angle of four degrees forty-seven minutes, theangle of their inclination to the same line when the end of the backwardstroke of the swing-jaw is attained would be measured by an arc whosesine is two and one-half inches. This, with a radius of fifteen inches,would be nine degrees thirty-six minutes, and the length of the strokewould beover three-tenths of an iucha stroke sufficiently great for thepractical work of stone-breaking on a large scale.

The length of the stroke of the swing-jaw having been adjusted asdesired, the adjustment of the opening at the bottom of the jaws is madeby screwing up or unscrewing the out on the main tension-rods at therear of the machine. It is evident, therefore, that an adjustable pitmancombined with a toggle-joint gives the means of adjusting the length ofthe stroke of the movable jaw within any reasonable working limitswithout substitution of parts.

The main shaft is provided with fly-wheels, and pulley or other means,for communicating power to the machine. The movable jaw A is withdrawnby means of a rubber spring, J, and rod K, which passes through atransverse timber, connecting the two parallel timbers on which the maincastings are cushioned, and hooks into an eye in the bottom of themovable jaw.

The timbers B B and the elastic cushions between them and the body ofthe machine or main castings form component parts of the machine. Theformer may be regarded as inverted beams, in which the front and rearparts or castings form the points of support, and the strain upon thepitman is the load. They act as springs. They are calculated to resistall normal strains upon the shaft, but are intended to yield by theirelasticity, and, in the case of undue strains, by compression of fibers.In case of such compression of the fibers, the machine may be readjustedby means of the nuts on the pitman and main tension-rods to thejaw-opening and length of stroke it is desirable to employ. The timbersB B may be replaced by an elastic beam or girder of wrought-iron. Thecushions a a. between the body and beams B B may be of rubber or otherelastic material, one-fourth to three-eighths of an inch in thickness.It is evident that the same result might be obtained by cushionin g themain shaft-boxes on the under side of the beams B B, or by a cushionabove the pitman-head block between the block and a plate on which thepitman-rod nuts should hear.

I have adopted the method of cushioning between the body and supportingtimbers or beams on account of its convenience, and of the largerbearing-surface there obtainable. The bearing-surfaces of the cushionsbeneath the body or main castings are so large, and the strain tendingto compress them so small, compared with that on the main tensionrods ofthe machine, that they will not yield materially under the strains onthe pitman incident to the ordinary work of stone-breaking, but willyield in case of an undue or excessive strain-such, for example, as theaccidental intrusion of a wedge-shaped piece of stone presenting anexceptionally large surface, or fragments of cast-iron, steel, or othermetals offering extraordinary resistance to compression. The result incase of such undue strains would be a stoppage of the motion of theswing-jaw before reaching the full limit of its ordinary stroke,combined with a subsequent partial revolution of the flywheels beforethey come to a fullstop, thus producing a great diminution of strains onthe parts of the machine, compared with those whose parts are so rigidthat the fly-wheels must under similar circumstances come almostinstantly to a stand-still and subject the parts of the machine tosudden and enormous strains, which must necessarily cause breakage.

It is evident that with a pitman of the construction described a greaternumber of rods may be used, or a single rod might be substituted for thetwo shown in the drawings.

I do not herein broadly claim an adjustable pitman in a stone-crusher,or such a pitman combined with an adjustable toggle-block, as I havemade broad claims to such construction in my application for LettersPatent filed April 9, 1879, such invention being shown in English PatentNo. 4,135, of 1877, and over which I claim priority, and propose toprove itin connection with said application of Aprili).

I claim-- 1. In a stone-breaking machine, the combination of a pair ofupright convergent jaws, mechanism for imparting a reciprocating orvibrating movement to one of said jaws, and an elastic or yieldingmaterial between said jaws and the point where the power takes itsbearing, substantially as described.

2. The combination of the block F and sliding head H with rod or rodsconnecting said head and block, and nuts and springs, so that theslidiug'of the head adjusts the length of the pitman, substantially asdescribed.

3. The combination, in a stone-breaking machine, ot' a pitman,adjustable as to its length with the toggle-block D, adjustable on therods E, substantially as described.

4. The combination, in a stone-breaking machine, of a pitman, with thetoggle-block D, adjustable on the rods E, substantially as described.

5. The combination,in a stone-breaking machine with upright convergentjaws, of the front and rear parts,.a tension bar or rod, E, at eachside, connecting said rear and front parts, and a clamp, O, embracingthe front part, each side the jaw-opening, substantially as described.

6. In a stone-breaking machine with upright convergent jaws, the clampsG (J, embracing the front part of the frame each side of the opening,substantially as described.

THEODORE AUGUSTUS BLAKE.

Witnesses:

JOHN E. EARLE, J. H. SHUMWAXZ.

